1. Field of the Invention
The invention relates to a wind engine, and more particularly to a wind engine formed by a multi-bladed, conical turbine, surrounded by a circulary deflector.
2. Background Art
The present wind engines FIG. 1) are generally constituted of a two- or three-bladed propeller rotating at the top of a pylon (2), and driving an electric generator (3) by means of a step-up gear (4).
The small pitch of the propellers together with their considerable weight imposes to start them by means of an auxiliary motor when the variable incidence blades, which are also operated by another auxiliary motor, are not sufficient. Their low rotation speed obliges to provide them with a coupling and with a high ratio step-up gear which is expressive and subject to wear. The whole has to be directed, without disturbing oscillations, into the direction of the wind, which imposes to use a new auxiliary motor and several correction members.
The successive automatisms often act adversely due to fast and repeated variations of the wind in intensity as well as in direction, resulting in a destruction of the best devices which have become moreover exaggeratedly expensive.
Not only the life of the parts which do most of the work doesn't reach ten years, but the growing dimensions of the propellers make their longevity uncertain even as the cost price of the generated energy being already too high.
The so-called American, multi-bladed propeller wheels FIG. 2), which are less fragile but very slow and which are still manufactured, especially for pumping water, have obtained the wrong idea, that they are on principle slow.
The maximum power of a wind engine is given by the formula of BET2: P.sub.max =0.37 SV.sup.3 wherein V=speed of wind and S=section of the airflow traversing the wind engine (FIG. 3). This surface S, generally called "the surface swept by the propeller" which expression is correct if the propeller intercepts the entire volume of the airflow, but incorrect if the blades subjected to the wind catch only a small part of the airflow (FIG. 3). This explains the small efficiencies of classical wind engines with respect to that surface (less than 30%). The manufacturers deluded with this unlucky expression, now run into the difficulties inherent to giant two-bladed propellers.
The multi-bladed wheels do not allow the air, that has worked and slowed down, to dilate when leaving the blades, moreover due to the fact that the peripheral wind (5, FIG. 4) beats the air back towards the center. The present invention is directed towards overcoming one or more of the problems discussed above.